Respiratory exercise device



FIG. 1 is a perspective view of a respiratory exercise device showing our new design;

FIG. 2 is a top plan view thereof;

FIG. 3 is a side elevation view thereof, the opposite side being a mirror image thereof;

FIG. 4 is a front elevation view thereof;

FIG. 5 is a rear elevation view thereof; and,

FIG. 6 is a bottom plan view thereof.

The broken lines that are immediately adjacent to the claimed areas depict the bounds of the claimed design while all other broken lines are directed to environment. The broken lines form no part of the claimed design. 

CLAIM The ornamental design for a respiratory exercise device, as shown and described. 